CRI DU CHAT SYNDROME

Description:

Cri du Chat syndrome is a rare genetic disorder where genetic material has been deleted from chromosome 5. It is also known as deletion 5p syndrome or 5p minus. "Jerome Lejeune diagnosed the first case of Cri du Chat in 1963."Cri Du Chat is a French name meaning "Cry of the Cat" this is because children that have the syndrome, ususally in their youth, cry out sounding like a cat's meow. "According to the 5p minus Society, approximately 50–60 children are born with cri du chat syndrome in the United States each year." People with different ethnic backgrounds have been know to have it. Even though it is found more commonly in women both men and women can have it. One way to definitely find out that someone has Cri du Chat syndrome is by blood testing and karyotyping.

Causes:

Cri Du Chat is caused by a chromosome number 5 abnormality. This abnormality involves the deletion of a part of the chromosome. 90% of this diesase is caused by random deletion of a piece of the chromosome. This means that it's herediatry deletion. However, 10% of this diesase involves a deletion which is because of a mistake in the choromosomal rearrangement. Meaning that it can be caused by a hereditary diesase. If this sydrome happens herediatrialy, the chance that a second child of these set of parents having Cri Du Chat is over 1%, if the occurence is spiratic, this set of parents have less than a 1% chance of a second child having the diesase.

external image CriDuChat.gif

Tokyo Medical University
The University of Utah

Can cri-du-chat syndrome be inherited?

Most cases of cri-du-chat syndrome are not inherited. They result from a chromosomal deletion that occurs as a random event during the formation of reproductive cells (eggs or sperm) or in early fetal development. Affected people typically have no history of the disorder in their family.
About 10 percent of people with cri-du-chat syndrome inherit the chromosome with a deleted segment from an unaffected parent. In these cases, the parent carries a chromosomal rearrangement called a balanced translocation, in which no genetic material is gained or lost. Balanced translocations usually do not cause any medical problems; however, they can become unbalanced as they are passed to the next generation. Children who inherit an unbalanced translocation can have a chromosomal rearrangement with extra or missing genetic material. Individuals with cri-du-chat syndrome who inherit an unbalanced translocation are missing genetic material from the short arm of chromosome 5, which results in birth defects and other health problems characteristic of this disorder.

Symptoms:

One of the most obvious symptoms of people with Cri Du Chat is a cry which is made by babies with this syndrom. This is due to an abnormal rate of growth of the larynx The cry is said to have a cat like quality, which is how the sydrome got the name "cry of the cat." As a child with Cri Du Chat grows, their larynx begins to develop normally. Therefore, as patients grow it is harder to detect the syndrome.
Another common symptom of Cri Du Chat that the patients have unusual facial features. These features, though unusual, can be subtle or noticeable. One of these features which is seen microchepaly(small head size).
CdC Support Group-www.criduchat.u-net.com
When a patient with cri du chat is young, they do not grow and develop at a normal rate.
Hypotonia or poor muscle tone is commonly found in children with cri du chat. This symptom oftens inhibits the development of eating habits.
About 30% of all children with Cri Du Chat suffer from congenital heart defect.
All patients with cri du chat show signs of mental retardation. However the level varies between cases.

Prognosis:

The prognosis for an infant with Cru Du Chat is only at a 10% mortality rate. This is due to the complications of symptoms such as hypotonia, congenital heart failure, and eating disorders. If these problems are able to be cured or aided, the lifespan of a person with Cru Du Chat is relatively normal. However, throughout life, problems with severe mental retardation can occur. There is new research showing that the severity of the retardation can be affected by the amount of therapy given to the patient.

Development:

The development of this disease in children varies. However most patients diagnosed with this disease share the slow development of speech, motor skills, and have an intellectual disability. Generally those with the disease are still fun-loving children who hold a special place in their respective families. Some of the major development issues are:

A short attention span
An intellectual disability with the majority of paitents ranging from moderate to severe
Many of the diagnosed patients have difficulty speaking, however they are more cabaple of understanding language than one would expect.
About a quarter of patients suffer from Hyper-activity
Harmful behavior such as: Biting, Scratching, Head-banging, and hitting.

Treatment:

There are no treatments for Cri du Chat so there is more focus on the medical care for the symptoms. Some of the symptoms that may occur are heart defects, chronic medical problems (ex. respiratory tract infections), and eating may become difficult. Symptoms like heart defects and chronic medical problems will require treatment or surgery. Eating may become difficult for children with Cri du Chat so a gastrostomy tube would have to be used to feed the child.